U.S. patent application number 15/657381 was filed with the patent office on 2018-02-01 for structure having metal material for heat radiation, printed circuit board, electronic apparatus, and metal material for heat radiation.
The applicant listed for this patent is JX NIPPON MINING & METALS CORPORATION. Invention is credited to HIDETA ARAI, ATSUSHI MIKI, SATORU MORIOKA.
Application Number | 20180035529 15/657381 |
Document ID | / |
Family ID | 61010597 |
Filed Date | 2018-02-01 |
United States Patent
Application |
20180035529 |
Kind Code |
A1 |
ARAI; HIDETA ; et
al. |
February 1, 2018 |
STRUCTURE HAVING METAL MATERIAL FOR HEAT RADIATION, PRINTED CIRCUIT
BOARD, ELECTRONIC APPARATUS, AND METAL MATERIAL FOR HEAT
RADIATION
Abstract
A structure having a metal material for heat radiation that is
capable of favorably radiating heat from a heat generating
component is provided. A structure having a metal material for heat
radiation, containing a heat generating component and a heat
radiating member for radiating heat from the heat generating
component, wherein the heat radiating member has a layer structure
containing a metal material for heat radiation and a graphite
sheet.
Inventors: |
ARAI; HIDETA; (IBARAKI,
JP) ; MIKI; ATSUSHI; (IBARAKI, JP) ; MORIOKA;
SATORU; (TOKYO, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
JX NIPPON MINING & METALS CORPORATION |
Tokyo |
|
JP |
|
|
Family ID: |
61010597 |
Appl. No.: |
15/657381 |
Filed: |
July 24, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28F 21/08 20130101;
H05K 2201/0323 20130101; H01L 23/3737 20130101; F28F 21/081
20130101; H05K 1/056 20130101; H01L 23/373 20130101; H05K 2201/0195
20130101; F28F 3/08 20130101; F28F 21/02 20130101; F28F 2013/006
20130101; H05K 1/0203 20130101 |
International
Class: |
H05K 1/02 20060101
H05K001/02; F28F 21/08 20060101 F28F021/08; F28F 3/08 20060101
F28F003/08; F28F 21/02 20060101 F28F021/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 27, 2016 |
JP |
2016-146866 |
Claims
1. A structure having a metal material for heat radiation,
comprising a heat generating component and a heat radiating member
for radiating heat from the heat generating component, wherein the
heat radiating member has a layer structure containing a metal
material for heat radiation and a graphite sheet.
2. The structure having a metal material for heat radiation
according to claim 1, wherein the heat radiating member contains
the graphite sheet and the metal material for heat radiation in
this order from the side of the heat generating component.
3. The structure having a metal material for heat radiation
according to claim 1, wherein the heat radiating member contains
the metal material for heat radiation and the graphite sheet in
this order from the side of the heat generating component.
4. The structure having a metal material for heat radiation
according to claim 2, wherein the heat radiating member contains a
plurality of the graphite sheets.
5. The structure having a metal material for heat radiation
according to claim 3, wherein the heat radiating member contains a
plurality of the graphite sheets.
6. The structure having a metal material for heat radiation
according to claim 1, wherein the heat radiating member contains
the graphite sheet, the metal material for heat radiation, and the
graphite sheet in this order from the side of the heat generating
component.
7. The structure having a metal material for heat radiation
according to claim 1, wherein the heat generating component is
disposed to face the entire surface of the heat radiating
member.
8. The structure having a metal material for heat radiation
according to claim 1, wherein the heat generating component
contains a heat generator and a heat generator protective member
provided to cover a part or the entire of the heat generator, and
the heat radiating member is provided on the side opposite to the
heat generator with respect to the heat generator protective
member.
9. The structure having a metal material for heat radiation
according to claim 6, wherein the structure further comprises a
thermal conductive resin between the heat generator and the heat
generator protective member.
10. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
contains a surface on the side of the heat generating component
and/or a surface on the side opposite to the heat generating
component that has a color difference .DELTA.L based on JIS 28730
satisfying .DELTA.L.ltoreq.-40.
11. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
contains a surface on the side of the heat generating component
and/or a surface on the side opposite to the heat generating
component that has a radiation factor of 0.03 or more.
12. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
contains a surface treatment layer provided on a surface on the
side of the heat generating component and/or a surface on the side
opposite to the heat generating component, and the surface
treatment layer contains one or more layers selected from the group
consisting of a roughening treatment layer, a heat resistant layer,
a rust preventing layer, a chromate treatment layer, a silane
coupling treatment layer, a plated layer, and a resin layer.
13. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
contains copper, a copper alloy, aluminum, an aluminum alloy, iron,
an iron alloy, nickel, a nickel alloy, gold, a gold alloy, silver,
a silver alloy, a platinum group metal, a platinum group metal
alloy, chromium, a chromium alloy, magnesium, a magnesium alloy,
tungsten, a tungsten alloy, molybdenum, a molybdenum alloy, lead, a
lead alloy, tantalum, a tantalum alloy, tin, a tin alloy, indium,
an indium alloy, zinc, or a zinc alloy.
14. The structure having a metal material for heat radiation
according to claim 13, wherein the metal material for heat
radiation contains copper, a copper alloy, aluminum, an aluminum
alloy, iron, an iron alloy, nickel, a nickel alloy, zinc, or a zinc
alloy.
15. The structure having a metal material for heat radiation
according to claim 14, wherein the metal material for heat
radiation contains phosphor bronze, Corson alloy, red brass, brass,
nickel silver, or other copper alloys.
16. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
is a metal strip, a metal plate, or a metal foil.
17. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
contains a surface on the side of the heat generating component
and/or a surface on the side opposite to the heat generating
component that has a surface roughness Sz of 5 .mu.m or more
measured with a laser microscope with laser light having a
wavelength of 405 nm.
18. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
contains a surface on the side of the heat generating component
and/or a surface on the side opposite to the heat generating
component that has a surface roughness Sa of 0.13 .mu.m or more
measured with a laser microscope with laser light having a
wavelength of 405 nm.
19. The structure having a metal material for heat radiation
according to claim 1, wherein the metal material for heat radiation
contains a surface on the side of the heat generating component
and/or a surface on the side opposite to the heat generating
component that has a surface roughness Sku of 6 or more measured
with a laser microscope with laser light having a wavelength of 405
nm.
20. The structure having a metal material for heat radiation
according to claim 1, wherein the heat radiating member further
contains a substance having thermal conductivity provided on the
side of the heat generating component.
21. The structure having a metal material for heat radiation
according to claim 20, wherein the substance has a thermal
conductivity of 0.5 W/(mK) or more.
22. A printed circuit board comprising the structure having a metal
material for heat radiation according to claim 1.
23. An electronic apparatus comprising the structure having a metal
material for heat radiation according to claim 1.
24. A metal material for heat radiation comprising one or more
surfaces, wherein at least one of the surfaces satisfies one or
more of the following items (1) to (5), and the metal material for
heat radiation is to be adhered with a graphite sheet and to be
used as a heat radiating member: (1) the surface having a color
difference .DELTA.L based on JIS 28730 of .DELTA.L.ltoreq.-40; (2)
the surface having a radiation factor of 0.03 or more; (3) the
surface having a surface roughness Sz of 5 .mu.m or more measured
with a laser microscope with laser light having a wavelength of 405
nm; (4) the surface having a surface roughness Sa of 0.13 .mu.m or
more measured with a laser microscope with laser light having a
wavelength of 405 nm; and (5) the surface having a surface
roughness Sku of 6 or more measured with a laser microscope with
laser light having a wavelength of 405 nm.
Description
[0001] In the present application, priority is claimed based on
Japanese Patent Application No. 2016-146866 filed on Jul. 27, 2016,
and the entire disclosure of the Japanese Patent Application is
incorporated herein by reference.
Technical Field
[0002] The present invention relates to a structure having a metal
material for heat radiation, a printed circuit board, an electronic
apparatus, and a metal material for heat radiation.
Background Art
[0003] Associated with the miniaturization and high definition of
electronic apparatuses in recent years, there are problems
including malfunctions and the like due to the heat generation of
the electronic component used therein.
[0004] In view of the problems, for example, PTL 1 describes the
research and development of the technique, in which a graphite
sheet, which is a heat radiating member having a high thermal
conductivity in the in-plane direction, is closely attached to the
heat generating component directly or through an adhesive
layer.
CITATION LIST
Patent Literature
[0005] PTL 1: JP-A-2013-021357
SUMMARY OF INVENTION
Technical Problem
[0006] The graphite sheet is effective as a heat radiating member,
but there is still room for development in a structure of a heat
radiating member capable of favorably radiating heat from a heat
generating component, other than the structure constituted only by
the graphite sheet.
[0007] Under the circumstances, an object of the invention is to
provide a structure having a metal material for heat radiation that
is capable of favorably radiating heat from a heat generating
component.
Solution to Problem
[0008] As a result of earnest investigations made by the present
inventors, it has been found that the object can be achieved by a
structure having a metal material for heat radiation having a
structure containing a heat generating component and a heat
radiating member for radiating heat from the heat generating
component, in which the heat radiating member is provided to have a
layer structure containing a metal material for heat radiation and
a graphite sheet.
[0009] The invention having been completed based on the
aforementioned knowledge provides, in one aspect, a structure
having a metal material for heat radiation, containing a heat
generating component and a heat radiating member for radiating heat
from the heat generating component, wherein the heat radiating
member has a layer structure containing a metal material for heat
radiation and a graphite sheet.
[0010] In the structure having a metal material for heat radiation
according to one embodiment of the invention, the heat radiating
member contains the graphite sheet and the metal material for heat
radiation in this order from the side of the heat generating
component.
[0011] In the structure having a metal material for heat radiation
according to another embodiment of the invention, the heat
radiating member contains the metal material for heat radiation and
the graphite sheet in this order from the side of the heat
generating component.
[0012] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the heat
radiating member contains a plurality of the graphite sheets.
[0013] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the heat
radiating member contains the graphite sheet, the metal material
for heat radiation, and the graphite sheet in this order from the
side of the heat generating component.
[0014] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the heat
generating component is disposed to face the entire surface of the
heat radiating member.
[0015] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the heat
generating component contains a heat generator and a heat generator
protective member provided to cover a part or the entire of the
heat generator, and the heat radiating member is disposed on the
side opposite to the heat generator with respect to the heat
generator protective member.
[0016] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the
structure further contains a thermal conductive resin between the
heat generator and the heat generator protective member.
[0017] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains a surface on the side of the
heat generating component and/or a surface on the side opposite to
the heat generating component that has a color difference .DELTA.L
based on JIS 28730 satisfying .DELTA.L.ltoreq.-40.
[0018] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains a surface on the side of the
heat generating component and/or a surface on the side opposite to
the heat generating component that has a radiation factor of 0.03
or more.
[0019] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains a surface treatment layer
provided on a surface on the side of the heat generating component
and/or a surface on the side opposite to the heat generating
component, and the surface treatment layer contains one or more
layers selected from the group consisting of a roughening treatment
layer, a heat resistant layer, a rust preventing layer, a chromate
treatment layer, a silane coupling treatment layer, a plated layer,
and a resin layer.
[0020] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains copper, a copper alloy,
aluminum, an aluminum alloy, iron, an iron alloy, nickel, a nickel
alloy, gold, a gold alloy, silver, a silver alloy, a platinum group
metal, a platinum group metal alloy, chromium, a chromium alloy,
magnesium, a magnesium alloy, tungsten, a tungsten alloy,
molybdenum, a molybdenum alloy, lead, a lead alloy, tantalum, a
tantalum alloy, tin, a tin alloy, indium, an indium alloy, zinc, or
a zinc alloy.
[0021] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains copper, a copper alloy,
aluminum, an aluminum alloy, iron, an iron alloy, nickel, a nickel
alloy, zinc, or a zinc alloy.
[0022] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains phosphor bronze, Corson alloy,
red brass, brass, nickel silver, or other copper alloys.
[0023] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation is a metal strip, a metal plate, or a
metal foil.
[0024] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains a surface on the side of the
heat generating component and/or a surface on the side opposite to
the heat generating component that has a surface roughness Sz of 5
.mu.m or more measured with a laser microscope with laser light
having a wavelength of 405 nm.
[0025] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains a surface on the side of the
heat generating component and/or a surface on the side opposite to
the heat generating component that has a surface roughness Sa of
0.13 .mu.m or more measured with a laser microscope with laser
light having a wavelength of 405 nm.
[0026] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the metal
material for heat radiation contains a surface on the side of the
heat generating component and/or a surface on the side opposite to
the heat generating component that has a surface roughness Sku of 6
or more measured with a laser microscope with laser light having a
wavelength of 405 nm.
[0027] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the heat
radiating member further contains a substance having thermal
conductivity provided on the side of the heat generating
component.
[0028] In the structure having a metal material for heat radiation
according to still another embodiment of the invention, the
substance has a thermal conductivity of 0.5 W/(mK) or more.
[0029] The invention provides, in another aspect, a printed circuit
board containing the structure having a metal material for heat
radiation according to the invention.
[0030] The invention provides, in still another aspect, an
electronic apparatus containing the structure having a metal
material for heat radiation according to the invention.
[0031] The invention provides, instill another aspect, a metal
material for heat radiation containing one or more surfaces,
wherein at least one of the surfaces satisfies one or more of the
following items (1) to (5), and the metal material for heat
radiation is to be adhered with a graphite sheet and to be used as
a heat radiating member:
[0032] (1) the surface having a color difference .DELTA.L based on
JIS Z8730 of .DELTA.L.ltoreq.-40;
[0033] (2) the surface having a radiation factor of 0.03 or
more;
[0034] (3) the surface having a surface roughness Sz of 5 .mu.m or
more measured with a laser microscope with laser light having a
wavelength of 405 nm;
[0035] (4) the surface having a surface roughness Sa of 0.13 .mu.m
or more measured with a laser microscope with laser light having a
wavelength of 405 nm; and
[0036] (5) the surface having a surface roughness Sku of 6 or more
measured with a laser microscope with laser light having a
wavelength of 405 nm.
Advantageous Effects of Invention
[0037] According to the invention, a structure having a metal
material for heat radiation can be provided that is capable of
favorably radiating heat from a heat generating component.
BRIEF DESCRIPTION OF DRAWINGS
[0038] FIG. 1 is a schematic cross sectional view showing the
structure having a metal material for heat radiation of Reference
Example.
[0039] FIG. 2 is a schematic cross sectional view showing the
structures having a metal material for heat radiation of Examples
1a to 1c.
[0040] FIG. 3 is a schematic cross sectional view showing the
structures having a metal material for heat radiation of Examples
2a to 2c.
[0041] FIG. 4 is a schematic cross sectional view showing the
structures having a metal material for heat radiation of Examples
3a to 3c.
[0042] FIG. 5 is an illustration showing the position of the heat
generator provided with respect to the heat radiating member in
Reference Example and Examples.
[0043] FIG. 6 is an illustration showing the maximum temperatures
of the outermost surfaces (heat radiating surfaces) of the heat
radiating members in Reference Example and Examples.
DESCRIPTION OF EMBODIMENTS
[0044] The structure having a metal material for heat radiation of
the invention contains a heat generating component and a heat
radiating member for radiating heat from the heat generating
component, in which the heat radiating member has a layer structure
containing a metal material for heat radiation and a graphite
sheet. The heat generating component means a member that generates
heat or a member containing as apart thereof the member that
generates heat, and is a concept that includes, for example, an
electric component, an application processor, an IC chip, and the
like.
[0045] The heat generating component may contain a heat generator
and a heat generator protective member provided to cover a part or
the entire of the heat generator, and the heat radiating member may
be disposed on the side opposite to the heat generator with respect
to the heat generator protective member. A thermal conductive resin
may be provided between the heat generator and the heat generator
protective member, and thereby the heat from the heat generator can
be efficiently conducted from the heat generator protective member
to the heat radiating member.
[0046] The heat generator protective member may be provided to
cover a part or the entire of the heat generating component, and
may have a concept that includes, for example, a heat generating
component cover, an electromagnetic wave shielding material, an
electromagnetic wave shielding cover, and the like. The heat
generator protective member may be any member that can absorb heat
and radiate the heat outward, and examples of the material used
therefor include various known materials including iron, copper,
aluminum, magnesium, nickel, vanadium, zinc, magnesium, titanium,
alloys of these metals, stainless steel, an inorganic material,
ceramics (such as silicon nitride) , a metal oxide, a compound, an
organic material, graphene, graphite, carbon nanotubes, black lead,
a conductive polymer, a high thermal conductive resin, a
polycarbonate resin, a polyamide resin, a polybutylene
terephthalate resin, a polyacetal resin, and a modified
polyphenylene ether resin. The heat generator protective member
preferably has thermal conductivity.
[0047] The heat radiating member of the structure having a metal
material for heat radiation of the invention has a layer structure
containing a metal material for heat radiation and a graphite
sheet. The metal material for heat radiation favorably conducts the
heat from the heat generating component not only in the horizontal
direction of the heat radiating member but also in the vertical
direction (i.e. , the thickness direction) thereof, and thus the
heat from the heat generating component can be radiated by
favorably conducting the heat from the heat radiating member toward
the upper surface. Accordingly, malfunction of the heat generating
component due to the temperature rise can be suppressed from
occurring.
[0048] In particular, mobile equipments, such as a smartphone and a
tablet PC, are being actively developed in recent years, and a
smartphone, a tablet PC, and the like are undergoing the increase
of the number of CPU mounted on the application processor and the
increase of the operation clock frequency thereof, for running high
load applications. The increase of the power consumption of the CPU
thereby increases the temperature of the application processor, and
actualizes the so-called "heat spot" problem, which causes low
temperature burn injury on carrying the smartphone. The
countermeasures for the heat spot include the decrease of the
operation clock frequency and the force quit of the application in
use on reaching a prescribed temperature, but these countermeasures
have a problem that the highly functional application processor
mounted cannot sufficiently exert the function thereof . The use of
the structure having a metal material for heat radiation of the
invention can radiate the heat from the application processor (heat
generating component) , and thus the temperature of the application
processor (heat generating component) can be favorably suppressed
from being increased, thereby sufficiently exerting the function of
the highly functional application processor.
[0049] In the structure having a metal material for heat radiation
of the invention, the heat radiating member may contain the
graphite sheet and the metal material for heat radiation in this
order from the side of the heat generating component. The heat
radiating member may contain the metal material for heat radiation
and the graphite sheet in this order from the side of the heat
generating component. The heat radiating member may contain the
graphite sheet, the metal material for heat radiation, and the
graphite sheet in this order from the side of the heat generating
component.
[0050] The heat radiating member and the heat generating component
may be fixed to each other by providing an adhesive tape (such as a
double-sided adhesive tape) between them. In the case where the
metal material for heat radiation and the heat generating component
can be fixed to each other through pressure bonding or the like,
the adhesive tape may not be provided.
[0051] In the structure having a metal material for heat radiation
of the invention, the heat generating component may be disposed to
face the entire surface of the heat radiating member. Such
constitution of the structure having a metal material for heat
radiation of the invention also can favorably radiate the heat from
the heat generator.
[0052] The heat radiating member of the structure having a metal
material for heat radiation of the invention may contain plural
graphite sheets. According to the constitution, the heat radiating
member may have better heat radiating property.
[0053] The metal material for heat radiation used in the invention
may be formed of copper, a copper alloy, aluminum, an aluminum
alloy, iron, an iron alloy, nickel, a nickel alloy, gold, a gold
alloy, silver, a silver alloy, a platinum group metal, a platinum
group metal alloy, chromium, a chromium alloy, magnesium, a
magnesium alloy, tungsten, a tungsten alloy, molybdenum, a
molybdenum alloy, lead, a lead alloy, tantalum, a tantalum alloy,
tin, a tin alloy, indium, an indium alloy, zinc, or a zinc
alloy.
[0054] The metal material for heat radiation may be a metal strip,
a metal plate, or a metal foil.
[0055] Typical examples of the copper include copper having a
purity of 95% by mass or more, more preferably 99.90% by mass or
more, for example, a phosphorus-deoxidized copper (JIS H3100, alloy
number: C1201, C1220, or C1221), an oxygen-free copper (JIS H3100,
alloy number: C1020), and a tough pitch copper (JIS H3100, alloy
number: C1100), and an electrolytic copper foil defined in JIS
H0500 and JIS H3100. Copper or a copper alloy containing one or
more of Sn, Ag, Au, Co, Cr, Fe, In, Ni, P, Si, Te, Ti, Zn, B, Mn,
and Zr in a total amount of from 0.001 to 4.0% by mass may also be
used.
[0056] Examples of the copper alloy include phosphor bronze, Corson
alloy, red brass, brass, nickel silver, and other copper alloys. As
the copper and the copper alloy, copper and copper alloys defined
in JIS H3100 to JIS H3510, JIS H5120, JIS H5121, JIS C2520 to JIS
C2801, and JIS E2101 to JIS E2102 can also be used in the
invention. In the description herein, the JISs cited for showing
the standards of metals are the JISs of the 2001 edition unless
otherwise indicated.
[0057] The phosphor bronze typically means a copper alloy
containing copper as the major component, Sn, and P in a smaller
amount than Sn. As one example, the phosphor copper may have a
composition containing from 3.5 to 11% by mass of Sn, from 0.03 to
0.35% by mass of P, and the balance of copper and unavoidable
impurities. The phosphor bronze may contain elements including Ni,
Zn, and the like in a total amount of 1.0% by mass or less.
[0058] The Corson alloy typically means a copper alloy containing
an element that forms a compound with Si (for example, one or more
of Ni, Co, and Cr) added thereto, which is precipitated as
secondary phase particles in the mother phase. As one example, the
Corson alloy may have a composition constituted by from 0.5 to 4.0%
by mass of Ni, from 0.1 to 1.3% by mass of Si, and the balance of
copper and unavoidable impurities. As another example, the Corson
alloy may have a composition constituted by from 0.5 to 4.0% by
mass of Ni, from 0.1 to 1.3% by mass of Si, from 0.03 to 0.5% by
mass of Cr, and the balance of copper and unavoidable impurities.
As still another example, the Corson alloy may have a composition
constituted by from 0.5 to 4.0% by mass of Ni, from 0.1 to 1.3% by
mass of Si, from 0.5 to 2.5% by mass of Co, and the balance of
copper and unavoidable impurities. As still another example, the
Corson alloy may have a composition constituted by from 0.5 to 4.0%
by mass of Ni, from 0.1 to 1.3% by mass of Si, from 0.5 to 2.5% by
mass of Co, from 0.03 to 0.5% by mass of Cr, and the balance of
copper and unavoidable impurities. As still another example, the
Corson alloy may have a composition constituted by from 0.2 to 1.3%
by mass of Si, from 0.5 to 2.5% by mass of Co, and the balance of
copper and unavoidable impurities. The Corson alloy may arbitrarily
contain other elements (such as Mg, Sn, B, Ti, Mn, Ag, P, Zn, As,
Sb, Be, Zr, Al, and Fe) added thereto. These elements may be added
generally in a total amount up to approximately 5.0% by mass. For
example, as still another example, the Corson alloy may have a
composition constituted by from 0.5 to 4.0% by mass of Ni, from 0.1
to 1.3% by mass of Si, from 0.01 to 2.0% by mass of Sn, from 0.01
to 2.0% by mass of Zn, and the balance of copper and unavoidable
impurities.
[0059] In the invention, the red brass means a copper alloy that is
an alloy of copper and zinc containing zinc in an amount of from 1
to 20% by mass, and preferably from 1 to 10% by mass. The red brass
may contain tin in an amount of from 0.1 to 1.0% by mass.
[0060] In the invention, the brass means a copper alloy that is an
alloy of copper and zinc particularly containing zinc in an amount
of 20% by mass or more. The upper limit of zinc is not particularly
limited, and may be 60% by mass or less, and preferably 45% by mass
or less or 40% by mass or less.
[0061] In the invention, the nickel silver means a copper alloy
containing copper as the major component, containing from 60% by
mass to 75% by mass of copper, from 8.5% by mass to 19.5% by mass
of nickel, and from 10% by mass to 30% by mass of zinc.
[0062] In the invention, the other copper alloys mean copper alloys
containing one kind or two or more kinds of Zn, Sn, Ni, Mg, Fe, Si,
P, Co, Mn, Zr, Ag, B, Cr, and Ti in a total amount of 8.0% by mass
or less, and the balance of copper and unavoidable impurities.
[0063] The aluminum and the aluminum alloy used may be, for
example, one containing A1 in an amount of 40% by mass or more, 80%
by mass or more, or 99% by mass or more. Examples thereof used
include aluminum and aluminum alloys defined in JIS H4000 to JIS
H4180, JIS H5202, JIS H5303, and JIS 23232 to JIS 23263. For
example, aluminum or an alloy thereof having an Al content of
99.00% by mass or more represented by the aluminum alloy numbers
1085, 1080, 1070, 1050, 1100, 1200, 1N00, and 1N30 defined in JIS
H4000 may be used.
[0064] The nickel and the nickel alloy used may be, for example,
ones containing Ni in an amount of 40% by mass or more, 80% by mass
or more, or 99.0% by mass or more. Examples thereof used include
nickel and nickel alloys defined in JIS H4541 to JIS H4554, JIS
H5701, JIS G7604 to JIS G7605, and JIS C2531. For example, nickel
or an alloy thereof having a Ni content of 99.0% by mass or more
represented by the alloy numbers NW 2200 and NW2201 defined in JIS
H4551 may be used.
[0065] The iron alloy used may be, for example, soft steel, carbon
steel, an iron-nickel alloy, steel, or the like. Examples thereof
used include iron and iron alloys defined in JIS G3101 to JIS
G7603, JIS C2502 to JIS C8380, JIS A5504 to JIS A6514, and JIS
E1101 to JIS E5402-1. The soft steel used may be soft steel having
a carbon content of 0.15% by mass or less, and soft steel described
in JIS G3141 and the like may be used. The iron-nickel alloy used
may contain Ni in an amount of from 35 to 85% by mass with the
balance of Fe and unavoidable impurities, and specifically may be
an iron-nickel alloy described in JIS C2531.
[0066] The zinc and the zinc alloy used may be, for example, ones
containing Zn in an amount of 40% by mass or more, 80% by mass or
more, or 99.0% by mass or more. Examples thereof used include zinc
and zinc alloys defined in JIS H2107 to JIS H5301.
[0067] The lead and the lead alloy used may be, for example, ones
containing Pb in an amount of 40% by mass or more, 80% by mass or
more, or 99.0% by mass or more. Examples thereof used include lead
and lead alloys defined in JIS H4301 to JIS H4312 and JIS
H5601.
[0068] The magnesium and the magnesium alloy used may be, for
example, ones containing Mg in an amount of 40% by mass or more,
80% by mass or more, or 99.0% by mass or more. Examples thereof
used include magnesium and magnesium alloys defined in JIS H4201 to
JIS H4204, JIS H5203 to JIS H5303, and JIS H6125.
[0069] The tungsten and the tungsten alloy used may be, for
example, ones containing W in an amount of 40% by mass or more, 80%
by mass or more, or 99.0% by mass or more. Examples thereof used
include tungsten and tungsten alloys defined in JIS H4463.
[0070] The molybdenum and the molybdenum alloy used may be, for
example, ones containing Mo in an amount of 40% by mass or more,
80% by mass or more, or 99.0% by mass or more.
[0071] The tantalum and the tantalum alloy used may be, for
example, ones containing Ta in an amount of 40% by mass or more,
80% by mass or more, or 99.0% by mass or more. Examples thereof
used include tantalum and tantalum alloys defined in JIS H4701.
[0072] The tin and the tin alloys used may be, for example, ones
containing Sn in an amount of 40% by mass or more, 80% by mass or
more, or 99.0% by mass or more. Examples thereof used include tin
and tin alloys defined in JIS H5401.
[0073] The indium and the indium alloy used may be, for example,
ones containing In in an amount of 40% by mass or more, 80% by mass
or more, or 99.0% by mass or more.
[0074] The chromium and the chromium alloy used may be, for
example, ones containing Cr in an amount of 40% by mass or more,
80% by mass or more, or 99.0% by mass or more.
[0075] The silver and the silver alloy used may be, for example,
ones containing Ag in an amount of 40% by mass or more, 80% by mass
or more, or 99.0% by mass or more.
[0076] The gold and the gold alloy used may be, for example, ones
containing Au in an amount of 40% by mass or more, 80% by mass or
more, or 99.0% by mass or more.
[0077] The platinum group is the generic name for ruthenium,
rhodium, palladium, osmium, iridium, and platinum. The platinum
group metal and the platinum group metal alloy used may be, for
example, ones containing at least one element selected from the
element group of Pt, Os, Ru, Pd, Ir, and Rh in an amount of 40% by
mass or more, 80% by mass or more, or 99.0% by mass or more.
[0078] The metal material for heat radiation preferably has a
thickness of 18 .mu.m or more. When the thickness of the metal
material for heat radiation is less than 18 .mu.m, there may be a
possibility that the sufficient heat radiation effect cannot be
obtained. The thickness of the metal material for heat radiation is
more preferably 35 .mu.m or more, further preferably 50 .mu.m or
more, still further preferably 65 .mu.m or more, and still further
preferably 70 .mu.m or more.
[0079] The surface of the metal material for heat radiation on the
side of the heat generating component and/or on the side opposite
to the heat generating component preferably has a surface roughness
Sz (i.e., the maximum height of the surface) of 5 .mu.m or more
measured with a laser microscope with laser light having a
wavelength of 405 nm. When the surface roughness Sz of the surface
of the metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component is less than 5 .mu.m, there may be a
possibility that the heat radiation property of the heat generating
component becomes inferior. The surface roughness Sz of the surface
of the metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component is preferably 7 .mu.m or more, more preferably
10 .mu.m or more, further preferably 14 .mu.m or more, still
further preferably 15 .mu.m or more, and still further preferably
25 .mu.m or more. The upper limit thereof is not particularly
determined, and may be, for example, 90 .mu.m or less, 80 .mu.m or
less, or 70 .mu.m or less. In the case where the surface roughness
Sz exceeds 90 .mu.m, there may be a case where the productivity is
reduced.
[0080] In the case where the metal material for heat radiation has
a surface treatment layer, such as a heat resistant layer, a rust
preventing layer, a chromate treatment layer, a silane coupling
treatment layer, and a resin layer, on the surface thereof, the
"surface on the side of the heat generating component" and the
"surface on the side opposite to the heat generating component " of
the metal material for heat radiation each mean the outermost
surface thereof after providing the surface treatment layer.
[0081] The surface of the metal material for heat radiation on the
side of the heat generating component and/or on the side opposite
to the heat generating component preferably has a surface roughness
Sa (i.e., the arithmetic average roughness of the surface) of 0.13
.mu.m or more. When the surface roughness Sa of the surface of the
metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component is less than 0.13 .mu.m, there may be a
possibility that the heat radiation property of the heat generating
component becomes inferior. The surface roughness Sa of the surface
of the metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component is more preferably 0.20 .mu.m or more, further
preferably 0.25 .mu.m or more, and still further preferably 0.30
.mu.m or more, and is typically from 0.1 to 1.0 .mu.m, and more
typically from 0.1 to 0.9 .mu.m.
[0082] The surface of the metal material for heat radiation on the
side of the heat generating component and/or on the side opposite
to the heat generating component preferably has a surface roughness
Sku (i.e. , the kurtosis of the surface height distribution;
kurtosis number) of 6 or more. When the Sku of the surface of the
metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component is less than 6, there may be a possibility
that the heat radiation property of the heat generating component
becomes inferior. The Sku of the surface of the metal material for
heat radiation on the side of the heat generating component and/or
on the side opposite to the heat generating component is more
preferably 9 or more, further preferably 10 or more, still further
preferably 40 or more, and still further preferably 60 or more, and
is typically from 3 to 200, and more typically from 4 to 180.
[0083] The surface of the metal material for heat radiation on the
side of the heat generating component and/or on the side opposite
to the heat generating component preferably has a color difference
.DELTA.L based on JIS Z8730 satisfying .DELTA.L.ltoreq.-40. When
the color difference .DELTA.L on the surface of the metal material
for heat radiation on the side of the heat generating component
and/or on the side opposite to the heat generating component is
controlled to satisfy .DELTA.L.ltoreq.-40, radiation heat,
convection heat, and the like generated from the heat generating
component can be favorably absorbed. The color difference AL
preferably satisfies .DELTA.L.ltoreq.-45, more preferably
.DELTA.L.ltoreq.-50, further preferably .DELTA.L.ltoreq.-55, still
further preferably .DELTA.L.ltoreq.-58, still further preferably
.DELTA.L.ltoreq.-60, still further preferably .DELTA.L.ltoreq.-65,
still further preferably .DELTA.L.ltoreq.-68, and still further
preferably .DELTA.L.ltoreq.-70. The lower limit of the .DELTA.L may
not be necessarily determined, and may satisfy, for example,
.DELTA.L.gtoreq.-90, .DELTA.L.gtoreq.-88, .DELTA.L.gtoreq.-85,
.DELTA.L.gtoreq.-83, .DELTA.L.gtoreq.-80, .DELTA.L.gtoreq.-78, or
.DELTA.L.gtoreq.-75. The color difference .DELTA.L based on JIS
Z8730 of the surface can be measured with a colorimeter, MiniScan
XE Plus, produced by Hunter Associates Laboratory, Inc.
[0084] The color difference .DELTA.L can be controlled, for
example, by using a copper material as a substrate of the metal
material for heat radiation, and forming roughening particles on
the surface of the copper material. The color difference .DELTA.L
can be achieved in such a manner that primary roughening particles
are formed by using an electrolytic solution containing at least
one element of copper, nickel, and cobalt at an increased current
density (for example, from 30 to 50 A/dm.sup.2) for a shortened
treatment time (for example, from 0.5 to 1.5 seconds) , and thereon
secondary roughening particles are formed at a high current density
(for example, from 20 to 40 A/dm.sup.2) for a short treatment time
(for example, from 0.1 to 0.5 seconds).
[0085] A surface treatment layer may be provided on the surface of
the metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component. The surface treatment layer may contain one
or more layers selected from the group consisting of a roughening
treatment layer, a heat resistant layer, a rust preventing layer, a
chromate treatment layer, a silane coupling treatment layer, a
plated layer, and a resin layer.
[0086] A roughening treatment for forming the roughening treatment
layer may be performed, for example, by forming roughening
particles with copper or a copper alloy. The roughening treatment
may be a fine treatment. The roughening treatment layer may be a
layer formed of an elemental substance of any one of copper,
nickel, cobalt, phosphorus, tungsten, arsenic, molybdenum,
chromium, and zinc, or an alloy containing one or more of them, or
the like. After forming the roughening particles with copper or a
copper alloy, a roughening treatment may be further performed to
provide secondary particles or tertiary particles with, for
example, an elemental substance or an alloy of nickel, cobalt,
copper, or zinc. Thereafter, a heat resistant layer or a rust
preventing layer maybe formed with, for example, an elemental
substance or an alloy of nickel, cobalt, copper, or zinc, and
further on the surface thereof, such treatments as a chromate
treatment, a silane coupling treatment, and the like may be
performed. In alternative, without a roughening treatment
performed, a plated layer may be formed, or a heat resistant layer
or a rust preventing layer may be formed with, for example, an
elemental substance or an alloy of nickel, cobalt, copper, or zinc,
and further on the surface thereof, such a treatment as a chromate
treatment, a silane coupling treatment, and the like may be
performed. Accordingly, one or more layer selected from the group
consisting of a heat resistant layer, a rust preventing layer, a
chromate treatment layer, a silane coupling treatment layer, a
plated layer, and a resin layer maybe formed on the surface of the
roughening treatment layer. The heat resistant layer, the rust
preventing layer, the chromate treatment layer, the silane coupling
treatment layer, the plated layer, and the resin layer each may be
formed of plural layers (for example, two or more layers, or three
or more layers). The plated layer can be formed by wet plating,
such as electro plating, electroless plating, and dip plating, or
dry plating, such as sputtering, CVD, and PDV.
[0087] The chromate treatment layer means a layer treated with a
liquid containing chromic anhydride, chromic acid, dichromic acid,
a chromate salt, or a dichromate salt. The chromate treatment layer
may contain such elements as cobalt, iron, nickel, molybdenum,
zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin,
arsenic, titanium, and the like (which may be in any form, for
example, a metal, an alloy, an oxide, a nitride, and a sulfide).
Specific examples of the chromate treatment layer include a
chromate treatment layer treated with an aqueous solution of
chromic anhydride or potassium dichromate, and a chromate treatment
layer treated with a treatment liquid containing chromic anhydride
or potassium dichromate and zinc.
[0088] The heat resistant layer and the rust preventing layer used
may be a known heat resistant layer and a known rust preventing
layer. For example, the heat resistant layer and/or the rust
preventing layer maybe a layer containing one or more element
selected from the group consisting of nickel, zinc, tin, cobalt,
molybdenum, copper, tungsten, phosphorus, arsenic, chromium,
vanadium, titanium, aluminum, gold, silver, a platinum group
element, iron, and tantalum, and may be a metal layer or an alloy
layer formed of one or more element selected from the group
consisting of nickel, zinc, tin, cobalt, molybdenum, copper,
tungsten, phosphorus, arsenic, chromium, vanadium, titanium,
aluminum, gold, silver, a platinum group element, iron, and
tantalum. The heat resistant layer and/or the rust preventing layer
may contain an oxide, a nitride, or a silicide of one or more
element selected from the group consisting of nickel, zinc, tin,
cobalt, molybdenum, copper, tungsten, phosphorus, arsenic,
chromium, vanadium, titanium, aluminum, gold, silver, a platinum
group element, iron, and tantalum. The heat resistant layer and/or
the rust preventing layer may be a layer containing a nickel-zinc
alloy. The heat resistant layer and/or the rust preventing layer
may be a nickel-zinc alloy layer. The heat resistant layer and/or
the rust preventing layer may be a layer of an organic material.
The layer of an organic material may contain one or more organic
material selected from the group consisting of a
nitrogen-containing organic compound, a sulfur-containing organic
compound, and a carboxylic acid. The nitrogen-containing organic
compound used is specifically preferably a triazole compound having
a substituent, such as 1,2,3-benzotriazole, carboxybenzotriazole,
N',N'-bis(benzotriazolylmethyl)urea, 1H-1,2,4-triazole, and
3-amino-1H-1,2,4-triazole. The sulfur-containing compound used is
preferably mercaptobenzothiazole, sodium 2-mercaptobenzothiazole,
thiocyanuric acid, or 2-benzimidazolthiol. The carboxylic acid used
is particularly preferably a monocarboxylic acid, and therein oleic
acid, linoleic acid, linolenic acid, or the like are preferably
used. The heat resistant layer and/or the rust preventing layer may
be a known organic rust preventing film containing carbon.
[0089] A silane coupling agent used for the silane coupling
treatment may be a known silane coupling agent, and examples
thereof used include an amino silane coupling agent, an epoxy
silane coupling agent, and a mercapto silane coupling agent.
Examples of the silane coupling agent used also include
vinyltrimethoxysilane, vinylphenyltrimethoxysilane,
.gamma.-methacryloxypropyltrimethoxysilane,
.gamma.-glycidoxypropyltrimethoxysilane,
4-glycidylbutyltrimethoxysilane,
.gamma.-aminopropyltriethoxysilane,
N-.beta.-(aminoethyl)-y-aminopropyltrimethoxysilane,
N-3-(4-(3-aminopropoxy)butoxy)propyl-3-aminopropyltrimetho
xysilane, imidazole silane, triazine silane, and
.gamma.-mercaptopropyltrimethoxysilane.
[0090] The resin layer used may be a layer containing a known
resin. The resin layer is preferably a resin layer containing a
resin that radiates heat. The resin used in the resin layer
preferably has a high radiation factor. The resin layer used may be
a known heat radiation sheet. The resin layer used may be a resin
layer containing one or more selected from the group consisting of
a silicone resin, an acrylic resin, a urethane resin,
ethylene-propylene-diene rubber, synthetic rubber, an epoxy resin,
a fluorine resin, a polyimide resin, a liquid crystal polymer, a
polyamide resin, a silicone oil, a silicone grease, and a silicone
oil compound. The resin layer may contain one or more selected from
the group consisting of a metal, ceramics, an inorganic material,
and an organic material, as a filler. The metal may be any one
metal selected from the group consisting of Ag, Cu, Ni, Zn, Au, Al,
a platinum group element, and Fe, or an alloy containing any one of
them. The ceramics may be one or more selected from the group
consisting of an oxide, a nitride, a silicide, and a carbide. The
oxide may contain one or more selected from the group consisting of
aluminum oxide, silicon oxide, zinc oxide, copper oxide, iron
oxide, zirconium oxide, beryllium oxide, titanium oxide, and nickel
oxide. The nitride may contain one or more selected from the group
consisting of boron nitride, aluminum nitride, silicon nitride, and
titanium nitride. The silicide may contain one or more selected
from the group consisting of silicon carbide, molybdenum silicide
(e.g., MoSi.sub.2 and Mo.sub.2Si.sub.3) , tungsten silicide (e.g.,
WSi.sub.2 and W.sub.5Si.sub.3), tantalum silicide (e.g.,
TaSi.sub.2), chromium silicide, and nickel silicide. The carbide
may contain one or more selected from the group consisting of
silicon carbide, tungsten carbide, calcium carbide, and boron
carbide. The inorganic material may contain one or more selected
from the group consisting of graphite, carbon nanotubes, fullerene,
diamond, graphene, and ferrite.
[0091] The surface of the metal material for heat radiation on the
side of the heat generating component and/or on the side opposite
to the heat generating component preferably has a radiation factor
of 0.03 or more. When the radiation factor of the surface of the
metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component is 0.03 or more, the heat from the heat
generating component can be favorably radiated. The radiation
factor of the surface of the metal material for heat radiation on
the side of the heat generating component and/or on the side
opposite to the heat generating component is more preferably 0.04
or more, more preferably 0.05 or more, more preferably 0.06 or
more, more preferably 0.092 or more, more preferably 0.10 or more,
further preferably 0.123 or more, further preferably 0.154 or more,
further preferably 0.185 or more, further preferably 0.246 or more,
preferably 0.3 or more, preferably 0.4 or more, preferably 0.5 or
more, preferably 0.6 or more, and preferably 0.7 or more.
[0092] The upper limit of the radiation factor of the surface of
the metal material for heat radiation on the side of the heat
generating component and/or on the side opposite to the heat
generating component may not be necessarily determined, and is
typically 1 or less, more typically 0.99 or less, more typically
0.95 or less, more typically 0.90 or less, more typically 0.85 or
less, and more typically 0.80 or less. When the radiation factor of
the surface of the metal material for heat radiation on the side of
the heat generating component and/or on the side opposite to the
heat generating component is 0.90 or less, the productivity may be
enhanced.
[0093] The metal material for heat radiation may be a metal
material for heat radiation containing one or more surfaces, at
least one of the surfaces may satisfy one or more of the following
items (1) to (5), and the metal material for heat radiation may be
adhered with a graphite sheet and to be used:
[0094] (1) the surface having a color difference .DELTA.L based on
JIS 28730 of .DELTA.L.ltoreq.-40;
[0095] (2) the surface having a radiation factor of 0.03 or
more;
[0096] (3) the surface having a surface roughness Sz of 5 .mu.m or
more measured with a laser microscope with laser light having a
wavelength of 405 nm;
[0097] (4) the surface having a surface roughness Sa of 0.13 .mu.m
or more measured with a laser microscope with laser light having a
wavelength of 405 nm; and
[0098] (5) the surface having a surface roughness Sku of 6 or more
measured with a laser microscope with laser light having a
wavelength of 405 nm.
[0099] The color difference .DELTA.L based on JIS 28730, the
radiation factor, and the surface roughnesses Sz, Sa, and Sku
measured with a laser microscope with laser light having a
wavelength of 405 nm of the surface of the metal material for heat
radiation are preferably controlled to the ranges of the color
difference .DELTA.L based on JIS 28730, the radiation factor, and
the surface roughnesses Sz, Sa, and Sku measured with a laser
microscope with laser light having a wavelength of 405 nm of the
surface of the metal material for heat radiation on the side of the
heat generating component, respectively. The metal material for
heat radiation can be adhered with a graphite sheet and can be used
as a heat radiating member.
[0100] In the structure having a metal material for heat radiation
of the invention, the heat radiating member may further contain a
substance having thermal conductivity on the face thereof on the
side of the heat generating component. According to the
constitution, the heat from the heat generating component can be
favorably radiated.
[0101] The substance having thermal conductivity used may be a
substance containing one or more selected from the group consisting
of a resin, a metal, ceramics, an inorganic material, and an
organic material. The resin used may be one or more selected from
the group consisting of a silicone resin, an acrylic resin, a
urethane resin, ethylene-propylene-diene rubber, synthetic rubber,
natural rubber, an epoxy resin, a polyethylene resin, a
polyphenylene sulfide (PPS) resin, a polybutylene terephthalate
(PBT) resin, a fluorine resin, a polyimide resin, a polycarbonate
resin, a liquid crystal polymer, a polyamide resin, a silicone oil,
a silicone grease, and a silicone oil compound. The resin may
contain one or more selected from the group consisting of a metal,
ceramics, an inorganic material, and an organic material, as a
filler. The metal, the ceramics, the inorganic material, and the
organic material may be the metal, the ceramics, the inorganic
material, and the organic material contained in the resin layer.
The form of the metal may be a bulk form, a particle form, a strand
form, a flake form, or a mesh form.
[0102] The substance having thermal conductivity preferably has a
thermal conductivity of 0 .5 W/ (mK) or more, preferably 1 W/ (mK)
or more, preferably 2 W/ (mK) or more, preferably 3 W/ (mK) or
more, preferably 5 W/ (mK) or more, preferably 10 W/ (mK) or more,
more preferably 20 W/ (mK) or more, more preferably 30 W/ (mK) or
more, and further preferably 35 W/ (mK) or more. The upper limit of
the thermal conductivity of the substance is not particularly
limited, and for example, 4,000 W/ (mK) or less, 3,000 W/ (mK) or
less, or 2,500 W/ (mK) or less. The thermal conductivity of the
substance having thermal conductivity is preferably the thermal
conductivity in the direction in parallel to the thickness
direction of the substance. The thickness direction of the
substance having thermal conductivity herein is the direction in
parallel to the thickness direction of the metal material for heat
radiation.
[0103] A printed wiring board can be produced by using the
structure having a metal material for heat radiation of the
invention, and a printed circuit board may be produced by mounting
electric components on the printed wiring board. An electronic
apparatus may be produced by using the printed circuit board, and
an electronic apparatus may be produced by using the printed
circuit board having electronic components mounted thereon. The
structure having a metal material for heat radiation of the
invention may be used for heat radiation of a heat generating
component of various electronic apparatuses, such as a display, a
IC chip, a capacitor, an inductor, a connector, a terminal, a
memory, an LSI, a chassis, a CPU, a circuit, and an integrated
circuit. For example, the structure having a metal material for
heat radiation can be used for heat radiation of an application
processor or the like of a mobile equipment, such as a smartphone
and a tablet PC, as the heat generating component.
EXAMPLES
[0104] 1. Preparation of Heat Radiating Member
[0105] As a heat radiating member, a graphite sheet having a
thickness of 25 .mu.m and the following metal materials for heat
radiation (thickness: 50 .mu.m, 70 .mu.m, and 100 .mu.m) were
prepared.
Metal Material for Heat Radiation
[0106] Metal material: copper substrate (rolled copper foil, having
a composition of a tough pitch copper defined in JIS H3100, alloy
number: C1100, having Ag added thereto in an amount of 200 ppm by
mass, obtained by repeatedly performing rolling and annealing, and
then rolling with an oil film equivalent amount of 25,000 in the
final cold rolling in the production of the rolled copper foil)
[0107] Surface treatment: electroplating treatments (performed (1)
and (2) in this order)
[0108] Plating solution conditions (1):
[0109] Cu concentration: 10 g/L, Sulfuric acid concentration: 20
g/L
[0110] pH: 1.0
[0111] Temperature: 26.degree. C.
[0112] Current density: 45 A/dm.sup.2
[0113] Plating time: 0.8 second.times.2
[0114] Current density: 4 A/dm.sup.2
[0115] Plating time: 2.0 seconds.times.2
[0116] Plating solution conditions (2):
[0117] Cu concentration: 8 g/L, Co concentration: 8 g/L, Ni
concentration: 8 g/L
[0118] pH: 3.5
[0119] Temperature: 35.degree. C.
[0120] Current density: 31 A/dm.sup.2
[0121] Plating time: 0.6 second.times.2
[0122] Thickness: 70
[0123] Color difference AL of the surface of the metal material for
heat radiation on the side of the heat generating component:
-54.2
[0124] Surface roughnesses of the surface of the metal material for
heat radiation on the side of the heat generating component, Sz:
25.1 .mu.m, Sa: 0.43 .mu.m, Sku: 21.4
[0125] The electroplated surfaces of the metal materials for heat
radiation were subjected to the heat resistant plating treatment
and the rust preventing plating treatment below.
Heat Resistant Plating Treatment
[0126] Ni concentration: 12 g/L, Co concentration: 3 g/L
[0127] pH: 2.0
[0128] Temperature: 50.degree. C.
[0129] Current density: 15 A/dm.sup.2
[0130] Plating time: 0.4 second.times.2
Rust Preventing Plating Treatment
[0131] Cr concentration: 3.0 gL/L, Zn concentration: 0.3 g/L
[0132] pH: 2.0
[0133] Temperature: 55.degree. C.
[0134] Current density: 2.0 A/dm.sup.2
[0135] Plating time: 0.5 second.times.2
Color Difference
[0136] The surfaces of the metal materials for heat radiation on
the side of the heat generating component were evaluated for the
color difference in the following manner.
[0137] The color difference of the surface of the metal material
for heat radiation on the side of the heat generating component
with respect to the object color of the white plate (assuming D65
as the light source and 10.degree. for the view field, the white
plate had tristimulus values of the X.sub.10Y.sub.10Z.sub.10
colorimetric system (JIS Z8701 1999) of X.sub.10=80.7,
Y.sub.10=85.6, Z.sub.10=91.5, and the white plate had an object
color of the L*a*b* colorimetric system of L*=94.14, a*=-0.90,
b*=0.24) as the standard color was measured according to JIS H8730
with a colorimeter, MiniScan XE Plus, produced by Hunter Associates
Laboratory, Inc. The color difference .DELTA.L herein is the color
difference that is in the case where the object color of the white
plate is the standard color, and is the color difference .DELTA.L
based on JIS Z8730 (i.e., the difference in CIE luminosity L* of
the two objects in the L* a* b* colorimetric system defined in JIS
28729 (2004)) . In the colorimeter, the color difference is
calibrated with .DELTA.E*ab=0 as the measured value of the color
difference of the white plate, and .DELTA.E*ab=94.14 as the
measured value of the color difference measured with the
measurement port covered with a black bag (light trap) . Herein,
the color difference .DELTA.E*ab is defined as 0 for the white
plate and 94.14 for black color. The color difference .DELTA.E*ab
according to JIS Z8730 of a microscopic area, such as a surface of
a copper circuit, can be measured with a known measurement
equipment, such as a microscopic area spectrophotometer (Model: VSS
400) , produced by Nippon Denshoku Industries Co., Ltd., and a
microscopic area spectrophotometer (Model: SC-50.mu.), produced by
Suga Test Instruments Co., Ltd.
Sz, Sa, and Sku of Surface
[0138] The surfaces of the metal materials for heat radiation on
the side of the heat generating component were evaluated for Sz,
Sa, and Sku in the following manner.
[0139] Sz, Sa, and Sku of the surface of the metal material for
heat radiation were measured according to ISO 25178 with a laser
microscope, OLS 4000 (LEXT OLS 4000) , produced by Olympus
Corporation. An area of approximately 200 .mu.m.times.200 .mu.m
(specifically 40,106 .mu.m.sup.2) was measured by using an
objective lens of a magnification of 50 of the laser microscope,
and Sz, Sa, and Sku were calculated. In the case where the
measurement surface of the measurement result became a curved
surface (not a flat surface) in the measurement with the laser
microscope, Sz, Sa, and Sku were calculated after performing the
plane correction. The environment temperature for the measurement
of Sz, Sa, and Sku with the laser microscope was from 23 to
25.degree.C.
[0140] 2. Production of Structure having Graphite for Heat
Radiation and Structure having Metal Material for Heat
Radiation
[0141] Subsequently, as shown in FIGS. 1 to 5, a structure having
graphite for heat radiation and structures having a metal material
for heat radiation were produced. In the following description, the
"high thermal conductive resin A" shows a silicone oil compound for
heat radiation, Model No. G-776, produced by Shin-Etsu Chemical
Co., Ltd., and the "high thermal conductive resin B" shows a
silicone resin, Denka Thermally Conductive Spacer, Grease Type,
grade: GFC-L1, produced by Denka Co., Ltd.
[0142] A heat generator (a heat generator containing heating wire
embedded in a resin, corresponding to an IC chip) having a size of
length.times.width.times.height=15 mm.times.15 mm.times.1 mm was
prepared, and the periphery of the heat generator was covered with
a heat generator protective member having a thickness of 200 .mu.m
formed of a stainless steel. The high thermal conductive resin B
was filled between the heat generator and the heat generator
protective member. The thickness of the high thermal conductive
resin B was 300 .mu.m while the thickness did not affect the heat
radiation test described later. The assembly of the heat generator,
the heat generator protective member, and the high thermal
conductive resin B was designated as the heat generating
component.
[0143] Subsequently, various heat radiating members were provided
on the face of the heat generator protective member on the side
opposite to the heat generator. The heat radiating member was
formed to have a size of length.times.width.times.thickness =50
mm.times.100 mm.times.(total thickness of layers). FIG. 5 shows the
position of the heat radiator provided with respect to the
horizontal plane (length.times.width=50 mm.times.100 mm) of the
heat radiating member. The heat generator was provided in such a
manner that the center of the heat generator was at the center in
the lengthwise direction of the heat radiating member and was
distant from one edge in the crosswise direction of the heat
radiating member by 15 mm.
Structure having Graphite for Heat Radiation of Reference
Example
[0144] In the structure having graphite for heat radiation of
Reference Example, as shown in FIG. 1, on the face of the heat
generator protective member on the side opposite to the heat
generator, from the side of the heat generator, the high thermal
conductive resin A having a thickness of 25 .mu.m, a double-sided
adhesive tape (film) using an acrylic adhesive having a thickness
of 20 .mu.m, a graphite sheet having a thickness of 25 .mu.m, a
double-sided adhesive tape (film) using an acrylic adhesive having
a thickness of 20 .mu.m, a graphite sheet having a thickness of 25
.mu.m, a double-sided adhesive tape (film) using an acrylic
adhesive having a thickness of 20 .mu.m, a graphite sheet having a
thickness of 25 .mu.m, and an acrylic adhesive having a thickness
of 20 .mu.m were provided as a heat radiating member, and an air
layer was further provided as the outermost layer.
Structures having Metal Material for Heat Radiation of Examples 1a,
1b, and 1c
[0145] In the structures having a metal material for heat radiation
of Examples 1a, 1b, and 1c, as shown in FIG. 2, on the face of the
heat generator protective member on the side opposite to the heat
generator, from the side of the heat generator, the high thermal
conductive resin A having a thickness of 25 .mu.m, a double-sided
adhesive tape (film) using an acrylic adhesive having a thickness
of 20 .mu.m, a graphite sheet having a thickness of 25 .mu.m, a
double-sided adhesive tape (film) using an acrylic adhesive having
a thickness of 20 .mu.m, a graphite sheet having a thickness of 25
.mu.m, a double-sided adhesive tape (adhesive layer/film) using an
acrylic adhesive having a thickness of 20 .mu.m, and the
aforementioned metal material for heat radiation having a thickness
of 50 .mu.m (Example 1a), 70 .mu.m (Example 1b), or 100 .mu.m
(Example 1c) were provided as a heat radiating member, and an air
layer was further provided as the outermost layer.
Structure having Metal Material for Heat Radiation of Example
1d
[0146] In the structure having a metal material for heat radiation
of, Example 1d, as shown in FIG. 2, on the face of the heat
generator protective member on the side opposite to the heat
generator, from the side of the heat generator, the high thermal
conductive resin A having a thickness of 25 .mu.m, a double-sided
adhesive tape (film) using an acrylic adhesive having a thickness
of 20 .mu.m, a graphite sheet having a thickness of 25 .mu.m, a
double-sided adhesive tape (film) using an acrylic adhesive having
a thickness of 20 .mu.m, a graphite sheet having a thickness of 25
.mu.m, a double-sided adhesive tape (adhesive layer/film) using an
acrylic adhesive having a thickness of 20 .mu.m, and the following
metal material for heat radiation having a thickness of 100 .mu.m
(Example 1d) were provided as a heat radiating member, and an air
layer was further provided as the outermost layer.
[0147] As the metal material for heat radiation of Example 1d, a
copper substrate (rolled copper foil, having a composition of a
tough pitch copper defined in JIS H3100, alloy number: C1100,
having Ag added thereto in an amount of 200 ppm by mass, obtained
by repeatedly performing rolling and annealing, and then rolling
with an oil film equivalent amount of 25,000 in the final cold
rolling in the production of the rolled copper foil) was used. A
rust preventing layer was provided on the surface of the copper
substrate. The rust preventing layer was an organic material layer
formed of 1,2,3-benzotriazole, which was a triazole compound having
a substituent.
Structures having Metal Material for Heat Radiation of Examples 2a,
2b, and 2c
[0148] In the structures having a metal material for heat radiation
of Examples 2a, 2b, and 2c, as shown in FIG. 3, on the face of the
heat generator protective member on the side opposite to the heat
generator, from the side of the heat generator, the high thermal
conductive resin A having a thickness of 25 .mu.m, a double-sided
adhesive tape (film) using an acrylic adhesive having a thickness
of 20 .mu.m, a graphite sheet having a thickness of 25 .mu.m, a
double-sided adhesive tape (adhesive layer/film) using an acrylic
adhesive having a thickness of 20 .mu.m, the same metal material
for heat radiation as used in Examples la, lb, and lc having a
thickness of 50 .mu.m (Example 2a) , 70 .mu.m (Example 2b) , or 100
.mu.m (Example 2c) , a double-sided adhesive tape (adhesive
layer/film) using an acrylic adhesive having a thickness of 20
.mu.m, a graphite sheet having a thickness of 25 .mu.m, and a PET
film (adhesive layer/film) having a thickness of 20 .mu.m were
provided as a heat radiating member, and an air layer was further
provided as the outermost layer.
Structure having Metal Material for Heat Radiation of Example
2d
[0149] In the structure having a metal material for heat radiation
of Example 2d, as shown in FIG. 3, on the face of the heat
generator protective member on the side opposite to the heat
generator, from the side of the heat generator, the high thermal
conductive resin A having a thickness of 25 .mu.m, a double-sided
adhesive tape (film) using an acrylic adhesive having a thickness
of 20 .mu.m, a graphite sheet having a thickness of 25 .mu.m, a
double-sided adhesive tape (adhesive layer/film) using an acrylic
adhesive having a thickness of 20 .mu.m, the following metal
material for heat radiation having a thickness of 100 .mu.m
(Example 2d), a double-sided adhesive tape (adhesive layer/film)
using an acrylic adhesive having a thickness of 20 .mu.m, a
graphite sheet having a thickness of 25 .mu.m, and a PET film
(adhesive layer/film) having a thickness of 20 .mu.m were provided
as a heat radiating member, and an air layer was further provided
as the outermost layer.
[0150] As the metal material for heat radiation of Example 2d, a
copper substrate (rolled copper foil, having a composition of a
tough pitch copper defined in JIS H3100, alloy number: C1100,
having Ag added thereto in an amount of 200 ppm by mass, obtained
by repeatedly performing rolling and annealing, and then rolling
with an oil film equivalent amount of 25,000 in the final cold
rolling in the production of the rolled copper foil) was used. A
rust preventing layer was provided on the surface of the copper
substrate. The rust preventing layer was an organic material layer
formed of 1,2,3-benzotriazole, which was a triazole compound having
a substituent.
Structures having Metal Material for Heat Radiation of Examples 3a,
3b, and 3c
[0151] In the structures having a metal material for heat radiation
of Examples 3a, 3b, and 3c, as shown in FIG. 4, on the face of the
heat generator protective member on the side opposite to the heat
generator, from the side of the heat generator, the high thermal
conductive resin A having a thickness of 25 .mu.m, the same metal
material for heat radiation as used in Examples la, lb, and lc
having a thickness of 50 .mu.m (Example 3a), 70 .mu.m (Example 3b),
or 100 .mu.m (Example 3c), a double-sided adhesive tape (adhesive
layer/film) using an acrylic adhesive having a thickness of 20
.mu.m, a graphite sheet having a thickness of 25 .mu.m, a
double-sided adhesive tape (adhesive layer/film) using an acrylic
adhesive having a thickness of 20 .mu.m, a graphite sheet having a
thickness of 25 .mu.m, and a PET film (film) having a thickness of
20 .mu.m were provided as a heat radiating member, and an air layer
was further provided as the outermost layer.
Structure having Metal Material for Heat Radiation of Example
3d
[0152] In the structure having a metal material for heat radiation
of Example 3d, as shown in FIG. 4, on the face of the heat
generator protective member on the side opposite to the heat
generator, from the side of the heat generator, the high thermal
conductive resin A having a thickness of 25 .mu.m, the following
metal material for heat radiation having a thickness of 100 .mu.m
(Example 3d), a double-sided adhesive tape (adhesive layer/film)
using an acrylic adhesive having a thickness of 20 .mu.m, a
graphite sheet having a thickness of 25 .mu.m, a double-sided
adhesive tape (adhesive layer/film) using an acrylic adhesive
having a thickness of 20 .mu.m, a graphite sheet having a thickness
of 25 .mu.m, and a PET film (film) having a thickness of 20 .mu.m
were provided as a heat radiating member, and an air layer was
further provided as the outermost layer.
[0153] As the metal material for heat radiation of Example 3d, a
copper substrate (rolled copper foil, having a composition of a
tough pitch copper defined in JIS H3100, alloy number: C1100,
having Ag added thereto in an amount of 200 ppm by mass, obtained
by repeatedly performing rolling and annealing, and then rolling
with an oil film equivalent amount of 25,000 in the final cold
rolling in the production of the rolled copper foil) was used. A
rust preventing layer was provided on the surface of the copper
substrate. The rust preventing layer was an organic material layer
formed of 1,2,3-benzotriazole, which was a triazole compound having
a substituent.
Measurement of Reflectance
[0154] The aforementioned specimens were measured for reflectances
to the wavelengths of light under the following condition. The
measurement was performed twice with the measurement direction
changed by 90.degree. within the measurement plane of the
specimen.
[0155] Measurement equipment: IFS-66v (FT-IR with vacuum optical
system, produced by Bruker Corporation)
[0156] Light source: Grover (SiC)
[0157] Detector: MCT (HgCdTe)
[0158] Beam splitter: Ge/KBr
[0159] Measurement condition: resolution: 4 cm.sup.-1
[0160] Cumulated number: 512
[0161] Zero filling: twice
[0162] Apodization: triangle
[0163] Measurement range: 5,000 to 715 cm.sup.-1 (light wavelength:
2 to 14 .mu.m)
[0164] Measurement temperature: 25.degree. C.
[0165] Auxiliary device: integrating sphere for measuring
transmittance and reflectance
[0166] Port diameter: 10 mm
[0167] Repetitive accuracy: ca. .+-.1%
[0168] Measurement condition for reflectance: [0169] Incident
angle: 10.degree. [0170] Reference specimen: diffuse gold
(Infragold-LF Assembly) [0171] Specular cup (specular component
removing device): not provided
Radiation Factor
[0172] Light incident on the specimen surface is reflected and
transmitted, and also is absorbed in the interior thereof. The
absorbance (.alpha.) (=radiation factor (.epsilon.)), the
reflectance (r), and the transmittance (t) satisfy the following
expression.
.epsilon.+r+t=1 (A)
[0173] The radiation factor (.epsilon.) can be obtained from the
reflectance and the transmittance according to the following
expression.
.epsilon.=1-r-t (B)
[0174] In the case where the specimen is opaque, or the
transmittance can be ignored due to the large thickness thereof,
t=0 is established, and the radiation factor can be obtained only
from the reflectance.
.epsilon.=1-r (C)
[0175] The expression (C) was applied to the specimen since the
specimen did not transmit an infrared ray, and the radiation
factors to the wavelengths of light were calculated.
FT-IR Spectrum
[0176] The average value of the results of the measurement
performed twice was designated as the reflectance spectrum. The
reflectance spectrum was calibrated with the reflectance of diffuse
gold (nominal wavelength region: 2 to 14 .mu.m).
[0177] Assuming that the energy intensity at the wavelength .lamda.
is E.sub.b.lamda., and the radiation factor of the specimen at the
wavelength .lamda. is .epsilon..lamda., the radiation energy
intensity of the specimen E.sub.s.lamda. is expressed by
E.sub.s.lamda.=.epsilon..lamda.E.sub.b.lamda., from a radiation
energy distribution of a blackbody at a certain temperature
obtained by the plank's expression. In the examples, the radiation
energy intensity E.sub.s.lamda., of the specimen at 25.degree. C.
was obtained by the expression
E.sub.s.lamda.=.epsilon..lamda.E.sub.b.lamda..
[0178] The total energy values of a blackbody and the specimen in a
certain wavelength range are obtained as the integrated values of
E.sub.s.lamda. and E.sub.b.lamda. in the wavelength range, and the
total radiation factor .epsilon. is expressed by the ratio thereof
(expression (A) below). In the examples, the total radiation factor
.epsilon. of the specimen in a wavelength range of from 2 to 14
.mu.m at 25.degree. C. was obtained by the expression. The total
radiation factor .epsilon. thus obtained was designated as the
radiation factor of the spcimen.
.epsilon.=.intg..sub..lamda.=2.sup..lamda.=14E.sub.s.lamda.d.lamda./.int-
g..sub..lamda.=2.sup..lamda.=14E.sub.b.lamda.d.lamda. (A)
[0179] The structures of Reference Example and Examples 1a to 3d
were subjected to heat radiation simulation under the following
conditions.
[0180] Steady analysis
[0181] The flux, the laminar flow, and the gravity were
considered.
[0182] Heat quantity of heat generator: 2.9 W
[0183] The lower side of the heat generator and the upper side of
the heat radiating member were set as the following heat radiation
conditions.
[0184] Environmental temperature: 20.degree. C.
[0185] Surface thermal conduction coefficient: 6 W/m.sup.2K
[0186] The wall opposite to the side receiving the radiation heat
was set as a blackbody at 20.degree. C.
[0187] The radiation in solid was not considered.
[0188] The calculation conditions and the property values are shown
in Table 1.
TABLE-US-00001 TABLE 1 Thermal Specific conduction Property of
Density heat coefficient Radiation material (kg/m.sup.3) (J/kg K)
(W/m K) factor Air assumed as ideal gas Stainless 7,930 590 16 0.1
steel Adhesive 1,200 1,470 0.16 0.9 layer/film (estimate value)
Metal 8,978 381 390 0.206 material for heat radiation Graphite 850
710 lengthwise -- sheet 3.5, crosswise 1,500 High thermal 1,900
1,400 1 -- conductive resin A High thermal 3,200 1,470 1 --
conductive resin B
[0189] The maximum temperatures of the outermost surfaces (heat
radiation surfaces) of the heat radiating members of Reference
Example and Examples, which are the results of the simulation, are
shown in FIG. 6.
Evaluation Results
[0190] All Examples 1a to 3d had the heat generator, the heat
generator protective member provided to cover a part or the entire
of the heat generator, and the heat radiating member disposed on
the side opposite to the heat generator with respect to the heat
generator protective member, in which the heat radiating member had
a layer structure containing the metal material for heat radiation
and the graphite sheet, and therefore were able to radiate
favorably the heat from the heat generator.
[0191] Examples 2a to 2d having the metal material for heat
radiation provided between the two layers of the graphite sheets
were more excellent in heat radiation effect than all the other
Examples, and Examples 1a to 1d having the metal material for heat
radiation provided far from the heat generator with respect to the
two layers of the graphite sheets were more excellent in heat
radiation effect than Examples 3a to 3d having the metal material
for heat radiation provided close to the heat generator with
respect to the two layers of the graphite sheets.
* * * * *